Machine for transforming the frequency of currents.



M. C. A. LATQUR & J. BETHENOD. MACHINE FOR TRANSFORMING THE FREQUENCY OFCURRENTS. APPLICATION FILED FEB. 20. 1914.

1 ,27 1,91 '5. Patented July 9, 1918.

6 haw/f (inf 2 UNITED STATES PATENT OFFICE.

MABIUS G. A. LATOUR AND JOSEPH IBETHENOD, 0F PARIS, FRANCE.

MACHINE FOR TRANSFORMING THE FREQUENCY OF CURRENTS.

Specification of Letters Patent.

Patented July 9, 1918.

Application filed February 20, 1914. Serial No. 820,088.

To all whom it may concern:

Be it known that we, MAmUs C. A. LATOUR and JOSEPH BETHENOD, engineers,residing in Paris, France, 10 Rue Auber, Paris, have This inventionrelates to apparatus for I transforming polyphase currents of nf cyclesinto polyphase currents of (n+2)f cycles by means of a singletransformation, a being any entire number whatever and f indicating theproper frequency of the machine used for the transformation.

It is known that in the case of the usual alternator the frequencycorresponds to the revolutions per second multiplied with the number ofpole pairs of the alternator. The alternator used in the presentinvention comprises a rotor with a single-phase winding which isshort-circuited and a stator with a two-phase winding. In theaccompanying drawing the alternator and its con nections arediagrammatically indicated. In the drawing B designates the rotor and Athe stator.

It is assumed that the terminals a, b, 03 are connected to any source Xfurnishing two-phase currents of the frequency nf. (The condensers 0indicated in the drawing have the purpose of suppressing orcounterbalancing the self induction of the windings to the frequencynf.) These two-phase currents of the frequency nf generate a fieldrotating with the velocity nf. Consequently, when the rotor turns, withthe angular velocity and in the opposite direction to the rotatingfield, a current of thefrequency of (n+1); is induced in its winding.This single phase current generates an alternating field which may beresolved in two rotating fields rotating in opposite directions at avelocity of (n+1) f with respect to the rotor. One of the two resolvedfields rotates with respect to the stator at a velocity of )ff="f andcombines its action in the usual manner with the stator field of thefrequency 'nf. while the other of the two fields rotates at a velocityof and induces consequentl in the windings of the stator at theternnnals a, b, d currents of the frequency (n+2) after the condensers cwhich, combined with the condensers 0 suppress the self induction of thestator windings at the frequency f. In this manner, while from theoutside source currents of the frequency nf are in- I troduced at theterminals a. b, and 03. currents of the higher frequency (n+2)f areobtained at the terminals a, b, (1. N aturally these currents of thefrequency (n+2) may again be transformed into currents of the frequency(n+4)f, etc.

While in the present invention reference is made to two-phase currentsit is understood that any polyphase current may be em loyed.

e claim:

A machine for transforming currents of lower frequency and currents ofhigher frequency for wireless telegraphy and telephony, comprising incombination a stator with a polyphase winding, a rotor with a singlephase winding, condensers connected to the stator and adapted to insureresonance of the circuit for the receiving current of the machine, andadditional condensers connected to the stator and in series to saidfirst named condensers and adapted to insure resonance ofthe circuit forthe current generated by the machine, substantially as described.

In testimony-whereof we aflix our signatures in presence of twowitnesses.

MARIUS C. A. LATOUR. JOSEPH BETHENOD. Witnesses:

CHAS. P. PRESSLY, EUGENE .VER'I'ANEN.

